Alumina hydroxide is now in demand across numerous industries. It's well-known for its stability, as seen in its various applications. Have you wondered what happens when this substance is added with phosphorus? Typically, it brings about these main effects. Below is a detailed introduction:
Phosphorus exists in an amorphous state on the surface of aluminum hydroxide, altering the quantity and nature of surface hydroxyl groups. This inhibition of the dehydroxylation sintering and particle growth of aluminum oxide enhances its thermal stability.
2. The stabilizing mechanism of phosphorus. The more uniformly distributed and firmly combined phosphorus is in alumina, the stronger its stabilizing effect. Different introduction methods of phosphorus alter the coordination situation of aluminum ions in alumina, with more hexacoordinated aluminum ions leading to greater stability of the active alumina regenerant.
3. Phosphorus exists in aluminum hydroxide in the form of monophosphate, inhibiting the bulk diffusion of aluminum ions, thereby increasing the α-phase transition temperature of alumina. Additionally, in a steam environment, Al-OH is replaced by the less removable P-OH, leading to a significant enhancement in the hydrothermal stability of active alumina.
In the hydrolysis and calcination processes, phosphorus changes from -3 to +5 valence, resulting in an increase of anionic vacancies, thereby enhancing the surface alkalinity.
Aluminum hydroxide, when added with phosphorus, offers numerous benefits, enhancing the product's stability. Consequently, it is typically necessary to add phosphorus during production to reinforce its molecular structure and prevent degradation. Products without phosphorus are generally superior. As a result, they are less prone to spoilage during use.
